Soil series profile
Kokomo soil series
Kokomo is a very poorly drained soil with a silty clay loam surface, mapped on 371,896 acres in 35 counties across 3 states. Hydrologic group C/D.
- Drainage class
- Very poorly drained 92% of mapped acres
- Hydrologic group
- C/D 98% of mapped acres
- Typical topsoil pH
- 6.2 slightly acidic · range 6.2–6.5
- Mapped area
- 372k acres in 35 counties, 3 states
Typical Kokomo profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–11 in (Ap) | Silty clay loam | 6.2 | 31% | 20% | 4.5% |
| 11–41 in (Btg) | Clay loam | 6.5 | 36% | 22% | 1.5% |
| 41–64 in (Bt) | Clay loam | 6.7 | 36% | 22% | 1.5% |
| 64–79 in (2C) | Loam | 7.9 | 22% | 40% | 0.1% |

What this means
What Kokomo soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Kokomo soils is slightly acidic: pH 6.2 (most land between 6.2 and 6.5), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 98% of mapped Kokomo acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silty clay loam (91% of mapped Kokomo acres).
98% of mapped Kokomo acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.
For lawns and yards
On 98% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.
A seasonal high water table comes within 18 inches of the surface on 98% of mapped acres, often in spring. Basements, sump pumps and lawns in low spots feel it first.
For a septic system
For conventional septic absorption fields, NRCS rates 98% of the acres in mapped Kokomo soils very limited, 0% somewhat limited and 0% not limited (2% not rated, such as urban land, pits or water).
Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Kokomo soil is found
Mapped acres
Kokomo is mapped in Ohio, Indiana and Michigan.
| County | Acres | Share of county land |
|---|---|---|
| Madison County, OH | 101,104 | 33.9% |
| Pickaway County, OH | 58,427 | 18.2% |
| Franklin County, OH | 42,646 | 12.4% |
| Preble County, OH | 41,836 | 15.4% |
| Clark County, OH | 36,790 | 14.5% |
| Ross County, OH | 19,015 | 4.3% |
| Clinton County, OH | 14,468 | 5.5% |
| Fayette County, OH | 9,361 | 3.6% |
| Darke County, OH | 6,490 | 1.7% |
| Miami County, OH | 5,762 | 2.2% |
| Champaign County, OH | 5,368 | 2.0% |
| Montgomery County, OH | 4,631 | 1.6% |
| Fairfield County, OH | 4,372 | 1.4% |
| Lenawee County, MI | 4,209 | 0.9% |
| Greene County, OH | 3,538 | 1.3% |
| Madison County, IN | 2,737 | 1.0% |
| Wayne County, IN | 2,726 | 1.1% |
| Hancock County, IN | 1,370 | 0.7% |
| Shelby County, OH | 1,268 | 0.5% |
| Logan County, OH | 1,010 | 0.3% |
| Howard County, IN | 956 | 0.5% |
| Henry County, IN | 793 | 0.3% |
| Ionia County, MI | 753 | 0.2% |
| Highland County, OH | 728 | 0.2% |
| Union County, OH | 607 | 0.2% |
| Butler County, OH | 394 | 0.1% |
| Shelby County, IN | 299 | 0.1% |
| Rush County, IN | 161 | 0.1% |
| Fayette County, IN | 46 | 0.0% |
| Decatur County, IN | 11 | 0.0% |
| Clinton County, IN | 9 | 0.0% |
| Union County, IN | 8 | 0.0% |
| Vigo County, IN | 3 | 0.0% |
| Tipton County, IN | 1 | 0.0% |
| Hocking County, OH | 0 | 0.0% |
Septic absorption fields
NRCS rating, share of Kokomo acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 98.0% |
| Not rated | 2.0% |
Drainage, water table and flooding
Share of Kokomo acres
- Depth to seasonal high water table
- About 2 inches (median where reported); within 18 inches on 98% of acres.
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 0–1% (median 1%).
- Topsoil organic matter
- Median 4.5%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 0.0% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 5.9% |
| Very poorly drained | 92.4% |
| Not rated | 1.8% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 0.0% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| A/D: D as is, A if drained | 0.0% |
| B/D: D as is, B if drained | 0.3% |
| C/D: D as is, C if drained | 97.7% |
| Not rated | 2.0% |
Sources & data dates
- Source
- USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
- Data date
- SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
- Scope
- All map unit components named Kokomo (component kind "Series") in SSURGO: 371,896 acres.
- Method
- Shares are by mapped acres of Kokomo components. The profile comes from the single largest Kokomo component. Full methodology.